JPH06303800A - Controller of generator, and method of operating and controlling generator - Google Patents

Abstract

PURPOSE:To maintain the output frequency of a generator constant independently of the rotating speed of a driving source to drive a generator. CONSTITUTION:A generator 16 is constituted of an object equipped with AC energizing winding, and the AC exciting winding of the generator 16 is supplied with the signals from an inverter 28. And, when controlling the output signal of the inverter 28, a rotational speed detector 24 detects the mechanical rotational speed of the generator 16, and a frequency detecting circuit 48 detects the system frequency being the frequency of the generator 16. And, an adder 50 seeks the deviation of each detected frequency, and a pulse making circuit 58 generates the pulse signal based on the signal geared to this deviation, and when the rotational speed of a turbine 22 changes by the accidents, etc., of an AC system, this controls the output frequency of the inverter 28, according to the deviation of frequency, and performs the variable-speed operation of the generator 16. Hereby, the output frequency of the generator can be synchronized to the frequency of the system independently of the rotational speed of the driving source, and the step-out of the generator can be prevented, and also the transit stability of the power system can be elevated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a generator control device and a generator operation control method, and more particularly to a generator control suitable for controlling the rotational speed of a generator that supplies electric power to an electric power transmission system. The present invention relates to an operation control method for a device and a generator.

[0002]

2. Description of the Related Art In recent years, it has been difficult to construct a new system in response to an increase in the grant of electric power in consideration of environmental problems and location conditions of power sources. As a concept to send electric power, FAC
TS (Flexible AC Transmission System) is under study.

In an electric power transmission system in which electric power of a generator is supplied to a load place via a transmission line, the electric power transmission limit of the transmission line is not determined by the heat capacity of the transmission line, but at the time of an accident, for example, the transmission line 3-line ground. It is determined from the transient stability because it is necessary to send power stably even when the transmission line is removed due to a power accident. And this value is a power much smaller than the heat capacity limit.

Specifically, as shown in FIG. 4, the electric power that can be transmitted through the power transmission line is determined by the impedance of the power transmission line that connects the generator and the load ground, and indicates the phase difference between the generator and the load value. The transmitted power changes according to the phase difference angle. This transmitted power is proportional to the output voltage of the generator and the voltage of the load ground, proportional to the phase difference angle, and inversely proportional to the impedance of the transmission line. Then, when the power transmission line is healthy, the transmitted power changes according to the characteristic Lx1. On the other hand, one of the two circuits due to a power line accident
When the line is removed, the transmitted power changes according to the characteristic Lx2. Then, the generator is normally operated at the phase difference angle δ0. When such operation is performed, the
When a ground fault occurs in the line, the output of the generator becomes zero, and the surplus energy of the turbine accelerates the generator. After that, when an accident is detected and the accident circuit is removed, if the phase difference angle of the generator opens to δc, the operating point moves from point a along the curve Lx2. At this time, energy corresponding to the area A1 is stored during the accident period, and the phase difference angle stops opening at point b when the energy A1 becomes equal to the deceleration energy A2. That is, the opening of the phase difference angle stops at the point where the energy is balanced. At this time, if the balance point exceeds point c, the generator loses step. In order to avoid such a step-out, the output of the generator is the impedance of the transmission line,
It is determined by the protection time and the system constant of the generator. vice versa,
The power for effectively transmitting the generator output determines the impedance of the transmission line, the protection time, and the like. In any case, when electric power is sent by a transmission line, it can be sent up to the maximum value of the transmission power at which the phase difference angle is 90 degrees, but considering the accident and stability of the transmission line, the generator output is the maximum value of the transmission power. Only half or less of the power can be sent.

[0005]

In the prior art, the fact that electric power is transmitted up to an allowable value that can be transmitted by a transmission line is not sufficiently considered, and the FACTS concept cannot be sufficiently dealt with. That is, in the conventional technology, no consideration is given to the variable speed operation of the generator in the event of a transmission line accident, and the generator is operated in a constant state. The output of the generator cannot be transmitted.

An object of the present invention is to provide a generator control device and a generator operation control method capable of maintaining a constant output frequency of the generator regardless of the rotation speed of a drive source for driving the generator. Especially.

[0007]

In order to achieve the above object, the present invention provides, as a first device, a drive source rotation speed for detecting a rotation speed of a drive source for driving a generator having an AC excitation winding. Detection means, generator frequency detection means for detecting the frequency of the output signal of the generator, frequency for suppressing the deviation between the detection value of the drive source rotation speed detection means and the detection value of the generator frequency detection means to zero A generator control device comprising a frequency signal generating means for generating a signal and an exciting means for exciting an AC exciting winding of the generator according to the frequency signal generated by the frequency signal generating means.

As a second device, turbine rotational speed detecting means for detecting the rotational speed of a turbine connected to a generator having an AC excitation winding, and a system for detecting a system frequency of an electric power system connected to the generator Frequency detection means, frequency signal generation means for generating a frequency signal for suppressing the deviation between the detection value of the turbine rotation speed detection means and the detection value of the system frequency detection means to zero, and the frequency generated by the frequency signal generation means A generator control device is provided, which comprises an excitation means for exciting the AC excitation winding of the generator according to a signal.

As a third device, a power detection means for detecting the output power of a generator having an AC excitation winding, and a deviation between a command value for the output of a turbine connected to the generator and a detection value of the power detection means. Drive source rotation speed calculating means for calculating the rotation speed of the drive source for driving the generator, system frequency detecting means for detecting the system frequency of the power system connected to the generator, and calculation of the drive source rotation speed calculating means Frequency signal generation means for generating a frequency signal for suppressing the deviation between the value and the detection value of the system frequency detection means to zero, and excites the AC excitation winding of the generator according to the frequency signal generated by the frequency signal generation means. And a magnetizing means for controlling the generator.

As a fourth device, a drive source rotation speed detecting means for detecting the rotation speed of a drive source for driving a generator having an AC excitation winding, and a generator frequency detection for detecting the frequency of an output signal of the generator. Means, frequency signal generating means for generating a frequency signal for suppressing the deviation between the detection value of the drive source rotation speed detecting means and the detection value of the generator frequency detecting means to zero, and the frequency generated by the frequency signal generating means. A frequency signal regulation unit that regulates the signal within the set value range of the generator rotation speed, and a governor that generates a governor control signal according to a frequency signal out of the set value range among the frequency signals generated by the frequency generation unit. Control signal generating means, steam amount control means for controlling the amount of steam to the turbine according to the governor control signal generated by the governor control signal generating means, and frequency signal regulating means. It is obtained by configuring the control apparatus of a generator and an excitation means for exciting the alternating excitation winding of the generator in accordance with regulated frequency signal within a range of values.

As a fifth device, turbine rotation speed detecting means for detecting a rotation speed of a turbine connected to a generator having an AC excitation winding, and a system for detecting a system frequency of an electric power system connected to the generator. Frequency detection means, frequency signal generation means for generating a frequency signal for suppressing the deviation between the detection value of the turbine rotation speed detection means and the detection value of the system frequency detection means to zero, and the frequency generated by the frequency signal generation means A frequency signal regulation unit that regulates the signal within the set value range of the generator rotation speed, and a governor that generates a governor control signal according to a frequency signal out of the set value range among the frequency signals generated by the frequency generation unit. Control signal generating means, steam amount control means for controlling the amount of steam to the turbine according to the governor control signal generated by the governor control signal generating means, and a frequency Is obtained by configuring the control apparatus of a generator and an excitation means for exciting the alternating excitation winding of the generator according to the range regulated frequency signal within the set value signal regulating means.

As a sixth device, a power detection means for detecting the output power of a generator having an AC excitation winding, and a deviation between a command value for the output of a turbine connected to the generator and a detection value of the power detection means. Drive source rotation speed calculating means for calculating the rotation speed of the drive source for driving the generator, system frequency detecting means for detecting the system frequency of the power system connected to the generator, and calculation of the drive source rotation speed calculating means Frequency signal generating means for generating a frequency signal for suppressing the deviation between the value and the detection value of the system frequency detecting means to zero, and the frequency signal generated by the frequency signal generating means within the set value range of the generator rotation speed. And a frequency control unit that generates a governor control signal according to a frequency signal out of the set value range among the frequency signals generated by the frequency generation unit. Stage, steam quantity control means for controlling the steam quantity to the turbine according to the governor control signal generated by the governor control signal generation means, and the generator according to the frequency signal regulated within the range of the set value by the frequency signal regulation means. The control device for the generator is provided with an exciting means for exciting the AC exciting winding.

As a seventh device, a voltage detecting means for detecting an output voltage of a generator having an AC excitation winding, a power detecting means for detecting an output power of the generator, a detection voltage of the voltage detecting means and a voltage command. Voltage deviation calculation means for calculating a deviation from the value, amplitude command generation means for generating an amplitude command for suppressing the calculation value of the voltage deviation calculation means to zero, detected power of the power detection means, and the power set value Power deviation calculating means for calculating the deviation, phase command generating means for generating a phase command for suppressing the calculated value of the power deviation calculating means to zero, and generator frequency detecting means for detecting the frequency of the output signal of the generator. When,
Drive source rotational speed detecting means for detecting the rotational speed of the drive source for driving the generator, and frequency deviation calculating means for calculating the deviation between the detected value of the drive source rotational speed detecting means and the detected value of the generator frequency detecting means. , A phase signal generating means for generating a phase signal for suppressing the value calculated by the frequency deviation calculating means to zero, and an addition for adding the phase signal generated by the phase signal generating means and the phase command generated by the phase command generating means Means, a pulse signal generating means for generating a pulse signal from the phase command generated by the addition of the adding means and the amplitude command generated by the amplitude command generating means, and the DC signal is converted into an AC signal in accordance with the pulse signal generated by the pulse signal generating means. Then, the control device for the generator is provided with a power conversion means for exciting the AC excitation winding of the generator with the converted AC signal.

As an eighth device, a voltage detecting means for detecting an output voltage of a generator having an AC excitation winding, a power detecting means for detecting an output power of the generator, a detection voltage of the voltage detecting means and a voltage command. Voltage deviation calculation means for calculating a deviation from the value, amplitude command generation means for generating an amplitude command for suppressing the calculation value of the voltage deviation calculation means to zero, detected power of the power detection means, and the power set value A power deviation calculating means for calculating the deviation, a phase command generating means for generating a phase command for suppressing the calculated value of the power deviation calculating means to zero, and a generator frequency detecting means for detecting the frequency of the generated power of the generator. When,
Auxiliary power deviation calculating means for calculating a deviation between a command value for the output of the turbine that rotationally drives the generator and the detected power of the power detecting means, and a rotation speed for suppressing the deviation of the auxiliary power deviation calculating means to zero. A rotation speed calculation means for calculating, a frequency deviation calculation means for calculating a deviation between a calculation value of the rotation speed calculation means and a detection value of the generator frequency detection means, and a value for suppressing the calculation value of the frequency deviation calculation means to zero. Phase signal generation means for generating a phase signal, addition means for adding the phase signal generated by the phase signal generation means and the phase command generated by the phase command generation means, and phase command and amplitude command generation means by the addition of the addition means Pulse signal generating means for generating a pulse signal from the amplitude command generated by the pulse signal generating means, and converting the DC signal into an AC signal according to the pulse signal generated by the pulse signal generating means It is obtained by configuring the control apparatus of a generator and a power converting means for exciting the alternating excitation winding of the generator with AC signal conversion.

As a ninth device including the seventh or eighth device, an amplitude command restricting means for restricting an amplitude command input to the pulse signal generating means within a set value range and a pulse signal generating means are inputted. And a phase command regulation unit that regulates the phase command within a set value range.

A tenth device including any one of the seventh, eighth, and ninth devices is a phase command out of a set value of phase commands input to the pulse signal generating means. Control device for a generator, which includes: a governor control signal generating means for generating a governor control signal according to the control signal; and a steam amount control means for controlling a steam amount to a turbine according to the governor control signal generated by the governor control signal generating means. Is configured.

As a first method, a generator having an AC excitation winding is rotationally driven according to the driving force of a driving source, and
The mechanical rotation speed of the generator is detected, the frequency of the power generated by the generator is further detected, a frequency signal is generated to suppress the deviation of each detected value to zero, and the AC excitation of the generator is performed according to this frequency signal. It employs a generator operation control method that excites the windings. .

As a second method, when a generator having an AC excitation winding is rotationally driven by a turbine and the AC excitation winding of the generator is excited by the output signal of the inverter,
Detects the mechanical rotation speed of the generator and the frequency of the generated power of the generator, generates a pulse signal to suppress the deviation of each detected value to zero, and according to this pulse signal, the frequency of the inverter output signal It employs a generator operation control method characterized by controlling

As a third method, when the generator having the AC excitation winding is rotationally driven by the turbine and the AC excitation winding of the generator is excited by the output signal of the inverter,
Detects the mechanical rotation speed of the generator and the frequency of the generated power of the generator, generates a pulse signal to suppress the deviation of each detected value to zero, and according to this pulse signal, the frequency of the inverter output signal The operation control method of the generator is characterized by controlling the amplitude of

As a fourth method, a designated generator among a plurality of generators is constituted by one having an AC excitation winding, and each generator is rotationally driven according to the driving force of a driving source, and designated. When exciting the AC excitation winding of the generator with the output signal of the inverter, the mechanical rotation speed of the specified generator is detected and the frequency of the generated power of the specified generator is detected,
The generator operation control method is characterized in that a pulse signal for suppressing the deviation of each detected value to zero is generated, and the frequency of the output signal of the inverter is controlled according to the pulse signal.

[0021]

According to the above-mentioned means, in order to operate the generator at a variable speed, a generator having an AC excitation winding is used. The mechanical design including such a generator is designed to have the highest efficiency at the rotation speed of the frequency synchronized with the frequency of the AC system. For this reason, the output of the generator is usually controlled so that it is synchronized with the frequency of the AC system, and the generator is AC-excited only when an accident occurs, and the generator is operated at a variable speed. The key is to prevent it. That is, when the generator is driven by the drive source, the rotation speed of the drive source is detected, the frequency of the output signal of the generator is detected, and the frequency signal for suppressing the deviation between the detected values of both is reduced to zero. To generate. Then, the AC excitation winding of the generator is excited in accordance with this frequency signal.

Specifically, as shown in FIG. 5, the magnetic fields of the rotor and the stator are changed to operate the generator at a variable speed. When the generator is operated at a variable speed, the electric speed Ns of the rotating magnetic field of the stator must always match (synchronize) with the frequency of the output signal of the generator (frequency of AC system). Therefore, when the acceleration energy of the generator becomes large due to an accident or the like, the mechanical rotation speed Nm of the rotor is accelerated (Nm> Ns), and when the deceleration energy of the generator becomes large due to the accident, the rotation speed Nm is reduced. (Nm <Ns). That is, Nm-Ne
When the rotor is AC-excited so that = Ns (Ne is the speed of the rotating magnetic field of the rotor), the electric speed of the rotating magnetic field of the rotor and the electric speed of the rotating magnetic field of the stator match (synchronize). Therefore, Nm is detected as the mechanical rotation speed of the drive source,
When Ns is detected as the frequency of the output signal of the generator, the deviation (Nm-Ns) between the detected values of the two is obtained, and the rotor is AC-excited by the frequency signal for suppressing this deviation to zero, the rotation of the drive source It is possible to always operate in synchronization with the frequency of the AC system regardless of the speed.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the infinity AC system 10 is connected to a generator 16 via a two-line AC power transmission line (one line is not shown) 12 and a transformer 14. Circuit breakers 18 and 20 are provided in the line of the AC power transmission line 12 to eliminate a line fault. The rotating shaft of the generator 16 is connected to a turbine 22 as a drive source, and a rotating speed detector 24 is provided on the rotating shaft of the turbine 22. The rotation speed detector 24 constitutes drive source rotation speed detection means and turbine rotation speed detection means for detecting the rotation speed of the turbine 22 as the mechanical rotation speed of the generator 16.

As shown in FIG. 2, the generator 16 includes an AC excitation winding RT, an armature winding ST, and a slip ring SL.
The AC excitation winding RT has a slip ring S
A signal from the inverter 28 is supplied via L. The inverter 28 is configured to include a GTO as a switching element capable of self-extinguishing and a diode Di, converts DC power from the DC power supply 30 into AC power, and converts the converted AC power into AC power via a slip ring SL. It is adapted to be supplied to the excitation winding RT. Further, the generator 16 drives the turbine 20 to rotate the rotor in accordance with the rotational speed of the turbine 22, and the stator has three
A rotating magnetic field is formed by the phase alternating current. Then, the rotation energy accompanying the rotation of the motor is converted into electric energy by the armature winding ST and transmitted to the transformer 14. When the rotor is driven by the turbine to rotate according to the rotating magnetic field of the stator, the rotation speed of the generator 16 is synchronized with the frequency of the AC system 10. on the other hand,
When the rotation speed of the turbine 22 is changed due to an accident of the AC power transmission line 12, it is supplied to the AC exciting winding RT of the generator 16 by the exciting means including the field winding 26 of the rotor, the inverter 28 and the DC power supply 30. The frequency of the excitation signal is controlled to operate the generator 16 at a variable speed. The frequency signal generating means for generating a frequency signal for operating the generator 16 at a variable speed and the generator frequency detecting means are configured as follows.

The frequency signal generating means comprises a constant voltage control system, a constant power control system, a frequency control system and a pulse signal generation system. The constant voltage control system includes a voltage detection circuit 32, a voltage command value 34, an adder 36, and an operational amplifier circuit 38. The constant power control system includes a power detection circuit 40 and an output setting device 4.
2, an adder 44 and an operational amplifier circuit 46, a frequency control system is composed of an adder 50, an operational amplifier circuit 52, a switch circuit 54 and an adder 56, and a pulse signal generation system is composed of a pulse generation circuit 58. ing.

The voltage detection circuit 32 is configured as voltage detection means for detecting the output voltage of the generator 16 and outputting the detected power to the adder 36. The adder 36 is the voltage detection circuit 3
The output signal of the adder 36 is input to the operational amplifier circuit 38, which is configured as a voltage deviation calculating unit that calculates the deviation between the detected voltage of 2 and the voltage command value 34. The operational amplifier circuit 38 is configured as an amplitude command generating unit that performs a proportional integral calculation on the signal from the adder 36 and generates an amplitude command for suppressing the voltage deviation to zero.

The power detection circuit 40 is constructed as a power detection means for detecting the output power of the generator 16 and outputting the detected power to the adder 44. The adder 44 is the output setting device 42
Is configured as a power deviation calculating unit that takes in the power set value with respect to the output power of the inverter 28 and the detected power of the power detection circuit 40 and calculates the deviation between the two, and the output signal of the adder 44 is input to the operational amplification circuit 46. Has been done.
The operational amplifier circuit 46 constitutes a phase command generating means for performing a proportional integral calculation on the output signal of the adder 44 and generating a phase command for suppressing the power deviation to zero. The output signal of the operational amplifier circuit 46 is input to the adder 56.

On the other hand, the adder 50 includes a rotation speed detector 24.
Detection signal is input and the frequency detection circuit 4
The detection signal from 8 is input. Frequency detection circuit 4
Reference numeral 8 is configured as a generator frequency detecting means that takes in a signal from the AC power transmission line 12, detects a system frequency that is a frequency of an output signal of the generator 16, and outputs a detection signal.
The adder 50 is configured as frequency deviation calculating means for calculating the deviation between the detection signal of the rotation speed detector 24 and the detection signal of the frequency detection circuit 48, and the output signal of the adder 50 is input to the operational amplification circuit 52. Has been done. The operational amplifier circuit 52 is configured as a phase signal generation unit that generates a phase signal for suppressing the frequency deviation signal from the adder 50 to zero. The output signal of the operational amplifier circuit 52 is input to the adder 56 via the switch circuit 54. The switch 54 is normally in an off state, and is turned on when a system fault detection signal or a transmission line fault detection signal is input as an external command C from a protective device in the event of a system fault or the like, and the operational amplifier circuit. The output signal of 52 is added to the adder 56
It is configured to output to. Then, the adder 56 receives the phase command signal from the operational amplifier circuit 46 and the operational amplifier circuit 5
The output signal of the adder 56 is input to the pulse generation circuit 58.

The pulse generation circuit 58 performs PWM based on the amplitude command from the operational amplifier circuit 38 and the phase command from the adder 56.
It is configured as pulse signal generation means for generating a signal. Specifically, the pulse generation circuit 58 uses the modulated wave signal MO.
A modulation wave signal generator that generates a carrier wave signal CA and a carrier wave signal generator that generates a carrier wave signal CA are provided. The amplitudes of the modulation wave signal MO and the carrier wave signal CA are compared, and a PWM signal is generated according to the comparison result. It is supposed to do. That is, a signal of "1" is output when the amplitude of the modulated wave signal MO> the amplitude of the carrier signal CA, and a signal of "0" is generated otherwise. When the PWM signal is "1", the GTO of the inverter 28 is turned on and "0"
It turns off when. Then, the amplitude command changes the amplitude of the modulated wave signal MO, and the phase command changes the frequency of the modulated wave signal MO or the carrier wave signal CA. When the amplitude and frequency are changed, the amplitude and frequency of the output voltage of the inverter 28 are controlled.

For example, according to the amplitude command, the modulated wave signal MO
When the amplitude of is increased, the PWM shown in FIG.
The pulse width of "1" of the signal becomes wider, and the inverter 2
The output voltage of 8 becomes high. On the other hand, if the phase command becomes large in a state where the amplitude command is constant, that is, the ratio (duty ratio) of the period in which the pulse of one cycle is on does not change, the frequencies of the modulated wave signal MO and the carrier signal CA become phase. The pulse width of the PWM signal becomes narrower in response to the command and becomes narrower. This increases the frequency of the output voltage of the inverter 28.

Next, the operation of the above embodiment will be described. When the AC power transmission line 12 is healthy, the turbine 22 is rotated at a constant rotation speed, and the output voltage and frequency of the generator 16 are controlled to be constant. In this case, the switch circuit 54 is in the OFF state, the PWM signal is generated according to the constant voltage control system and the constant power control system, the signal of the set voltage is output from the inverter 28, and the exciting current corresponding to the set voltage is generated. It flows through the AC excitation winding RT. In this case, a DC current will flow through the AC excitation winding RT.

On the other hand, when a ground fault or the like occurs in the AC power transmission line 12 and the output voltage of the generator 16 becomes zero, the turbine 22
Is accelerated by surplus energy. The rotation speed of the rotor of the generator 16 is also accelerated by the acceleration of the turbine 22, but the switch circuit 54 is closed by the external command C at this time, so the generator 1 detected by the rotation speed detector 24 is used.
The phase command according to the deviation of the frequency of the AC system detected by the mechanical rotation speed 6 and the frequency detection circuit 48 is added by the adder 5
Is added to 6. At this time, when the frequency deviation is large, the frequency of the output signal of the inverter 28 increases by that amount, and the phase difference angle of the generator 16 is opened to increase the output power of the generator 16.

However, even if the rotor of the generator 16 is accelerated, as shown in FIG. 5, an AC signal for suppressing frequency deviation flows from the inverter 28 to the AC exciting winding RT, and the rotor rotates. The magnetic field is formed so as to cancel the change in the rotating magnetic field on the stator side. Therefore, the turbine 22
Even if the rotation speed of the generator 16 changes, the speed of the generator 16 is variable so that the frequency of the output signal of the generator 16 always synchronizes with the frequency of the AC system 10.
Will never get out of step. When the generator 16 decelerates, the above operation is reversed, and in this case as well, the turbine 22
It is possible to synchronize the frequency of the output signal of the generator 16 with the system frequency of the AC system 10 regardless of the decrease in the rotation speed.

In the above embodiment, the switch circuit 54
The switch circuit 54 is turned on by an external command C, the timer is started from the time when the external command C is input, and the time set by the timer is turned on. It can also be configured to turn off when is passed. Further, as the timing of turning off, the turbine 22 may be turned off when the rotational speed of the turbine 22 returns to the normal rotational speed.

In the above embodiment, the switch circuit 54 is turned on at the time of an accident, and the phase signal corresponding to the frequency deviation is added to the adder 56 mainly at the time of the accident. The switch circuit 54 may be omitted and the output of the operational amplifier circuit 52 may be directly connected to the adder 56.

Next, a second embodiment of the present invention will be described with reference to FIG. In this embodiment, the rotation speed detector 24 is not used, and the mechanical rotation speed of the generator 16 is detected based on the detected power value. Other configurations are the same as those in FIG. Therefore, the same components as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted.

That is, the adder 62 and the operational amplifier circuit 64 are provided on the input side of the adder 50.
A signal relating to the detected electric power from the electric power detection circuit 40 and the mechanical input command value Pm input to the turbine speed control circuit 60 is input to the. This adder 62 is the turbine 22
Is configured as an auxiliary power deviation calculating means for calculating a deviation between the mechanical input command value Pn which is a command value for the output of the power detection circuit and the detected power Pe of the power detection circuit 40, and the output signal of the adder 62 is the operational amplification circuit 64. Has been entered in. The operational amplifier circuit 64 is configured as a rotation speed calculation unit that performs a proportional integration calculation on the signal from the adder 62 to calculate a rotation speed for suppressing the deviation of the power to zero.
The output signal of the operational amplifier circuit 64 is input to the adder 50.

Here, the rotation speed of the generator 16 is ω,
Let M be an inertia constant of a mechanical system including the generator 16, and the generator 1
When the output power of 6 is Pe and the mechanical input command value is Pm, the rotation speed ω of the generator 16 is obtained by time integration of (Pm-Pe) as shown in the following equation.

[0039]

[Equation 1]

According to this embodiment, the frequency of the output signal of the generator 16 is set to the AC system 1 regardless of the rotation speed of the turbine 22.
It can always be synchronized with the grid frequency of 0,
Even if the mechanical rotation speed of the turbine 16 is not directly detected,
The mechanical rotation speed of the generator 16 can be calculated based on the detected power value.

Next, a third embodiment of the present invention will be described with reference to FIG. In this embodiment, a limiter circuit 66 is provided as an amplitude command restricting means and a limiter circuit 68 is provided as a phase command restricting means on the input side of the pulse generating circuit 58, and other configurations are the same as those in FIG. , Only the main part is shown.

The limiter circuit 66 is configured to regulate the amplitude command output from the operational amplifier circuit 38 within the range of the set value, and the limiter circuit 68 controls the phase command from the adder 56 within the range of the set value. It is configured to regulate. When the pulse generation circuit 58 generates the PWM signal in accordance with the amplitude command and the phase command output from the limiter circuits 66 and 68, the upper limit and the lower limit of the amplitude and frequency of the output signal of the inverter 28 are also limited. Therefore, the capacity of the inverter 28 can be suppressed from increasing.

In the above embodiment, the operational amplifier circuit 38 is used.
While the limiter circuits 66 and 68 are provided on the output side of the adder 56, the operational amplifier circuits 38, 46 and 5 have been described.
It is also possible to provide a limiter circuit in 2. In this case, even if each operational amplifier circuit is saturated by the limiter circuit,
The return from saturation becomes faster, and the control response can be made faster than that in FIG. 7. Further, when a limiter circuit is provided, it can be applied to that of FIG.

Next, a fourth embodiment of the present invention will be described with reference to FIG. In the present embodiment, a comparison circuit 70 is provided on the output side of the adder 56, and the vapor amount control system 72 is controlled by the output signal of the comparison circuit 70. Other configurations are the same as in FIG. Therefore, only the configuration of the main part is shown.

The comparator circuit 70, when the phase command of the output of the adder 56 is out of the range of the set value of the limiter circuit 68,
It is configured as a governor control signal generation unit that generates a governor control signal according to a phase command that is out of the range of the set value. When the governor control signal is output from the comparison circuit 70 to the steam amount control system 72, the steam amount of the turbine is controlled according to the governor control signal. For example, when the phase command exceeds the upper limit value of the limiter circuit 68, the turbine 22
The amount of steam is controlled so as to decrease the rotation speed of No. 1, and conversely, when the phase command falls below the lower limit value of the limiter circuit 68, the amount of steam is controlled so as to increase the rotation speed of the turbine 22.

In the present embodiment, even when the rotational speed of the generator 16 cannot be controlled only by exciting the AC excitation winding RT of the generator 16, power is generated by controlling the amount of steam to the turbine 22. The rotation speed of the machine 16 can be maintained in a stable state.

Next, a fifth embodiment of the present invention will be described with reference to FIG. In the present embodiment, the amplitude command and the phase command are combined by the arithmetic circuit 74, and the PWM signal is generated according to the combined signal. Since the other configurations are the same as those in FIG. The configuration is shown.

The arithmetic circuit 74 synthesizes the amplitude command from the operational amplifier circuit 38 and the phase command from the adder 56, and outputs the synthesized signal to the pulse generating circuit 58. And when synthesizing the amplitude command and the phase command,
It is supposed to synthesize according to the following formula.

[0049]

[Equation 2]

Here, A indicates the output signal of the operational amplifier circuit 38, B indicates the output signal of the adder 56, X indicates the amplitude command to the pulse generating circuit 58, and Y indicates the phase command.

The arithmetic expression synthesized by the arithmetic circuit 74 is represented by the above equation because the signal of the power control system is the same direction component as the voltage of the AC system, and the signal of the voltage control system is the same as that of the AC system 10. This is because the phase is different from the voltage by 90 degrees.

According to this embodiment, since the power control system and the voltage control system do not interfere with each other, it is possible to construct a control system having a quick response.

A sixth embodiment of the present invention will be described with reference to FIG. In this embodiment, a plurality of generators 16A, 16B, 16
When power is supplied to the AC system 10 by C, the control system of FIG. 1 is applied to the generator 16A having the smallest capacity.

In the present embodiment, the frequency of the system is determined by the rotation of the generators 16B and 16C having a large capacity,
By operating the generator 16A at a variable speed in the event of a system accident, the energy associated with the accident can be absorbed or released, and the transient stability of the power system can be increased. That is, the transient stability of the power system can be enhanced by finely adjusting the system frequency by the variable speed operation of the generator 16A having a small capacity.

Generally, the generator is provided with a turbine, an exciter, etc., and the inertia constant becomes large. Therefore, it is possible to absorb and release energy by changing the rotation speed without attaching a flywheel to the generator. You can

Further, in each of the above-described embodiments, even if a ground fault occurs in the AC-phase electric wire 12, the generator 16 is not operated at a variable speed and out-of-step does not occur. There is no need to limit the electric power, and electric power can be transmitted from the generator 16 to the allowable electric power of the AC power transmission line 12.

[0057]

As described above, according to the present invention,
Since the frequency of the output signal of the generator can be kept constant regardless of the rotation speed of the drive source that drives the generator, out-of-step of the generator can be prevented and transient stability of the output system of the generator can be prevented. Can be increased. Further, electric power can be transmitted from the generator up to the allowable power of the output system of the generator.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram showing a first embodiment of the present invention.

FIG. 2 is a configuration diagram of an excitation system of a generator.

FIG. 3 is a waveform diagram for explaining the operation of the pulse generation circuit.

FIG. 4 is a characteristic diagram showing a relationship between a phase difference angle and transmitted power.

FIG. 5 is a diagram for explaining a state of a magnetic field acting on a rotor and a stator.

FIG. 6 is a main part configuration diagram showing a second embodiment of the present invention.

FIG. 7 is a main part configuration diagram showing a third embodiment of the present invention.

FIG. 8 is a main part configuration diagram showing a fourth embodiment of the present invention.

FIG. 9 is a main part configuration diagram showing a fifth embodiment of the present invention.

FIG. 10 is an overall configuration diagram showing a sixth embodiment of the present invention.

[Explanation of symbols]

 10 infinity AC system 12 AC transmission line 14 Transformer 16 Generator 22 Turbine 24 Rotational speed detector 28 Inverter 30 DC power supply 32 Voltage detection circuit 36 Adder 38 Operation amplification circuit 40 Power detection circuit 44 Adder 46 Operation amplification circuit 48 Frequency detection circuit 50 Adder 52 Operational amplifier circuit 56 Adder 58 Pulse creation circuit

Claims (14)

[Claims] 1. A drive source rotation speed detection means for detecting a rotation speed of a drive source for driving a generator having an AC excitation winding, a generator frequency detection means for detecting a frequency of an output signal of the generator, and a drive. Frequency signal generation means for generating a frequency signal for suppressing the deviation between the detection value of the source rotation speed detection means and the detection value of the generator frequency detection means to zero, and the power generation according to the frequency signal generated by the frequency signal generation means. And an excitation means for exciting an AC excitation winding of the machine. 2. A turbine rotation speed detecting means for detecting a rotation speed of a turbine connected to a generator having an AC excitation winding, and a system frequency detecting means for detecting a system frequency of an electric power system connected to the generator. A frequency signal generating means for generating a frequency signal for suppressing a deviation between a detected value of the turbine rotation speed detecting means and a detected value of the system frequency detecting means to zero; and the power generation according to the frequency signal generated by the frequency signal generating means. And an excitation means for exciting an AC excitation winding of the machine. 3. A power generator for detecting an output power of a generator having an AC excitation winding, and a generator from a deviation between a command value for an output of a turbine connected to the generator and a detected value of the power detector. Drive source rotation speed calculation means for calculating the rotation speed of the drive source to be driven, system frequency detection means for detecting the system frequency of the power system connected to the generator, calculated value of the drive source rotation speed calculation means and system frequency Frequency signal generating means for generating a frequency signal for suppressing the deviation from the detection value of the detecting means to zero, and exciting means for exciting the AC exciting winding of the generator according to the frequency signal generated by the frequency signal generating means. Generator control device equipped with. 4. A drive source rotation speed detection means for detecting a rotation speed of a drive source for driving a generator having an AC excitation winding, a generator frequency detection means for detecting a frequency of an output signal of the generator, and a drive. A frequency signal generating means for generating a frequency signal for suppressing the deviation between the detected value of the source rotation speed detecting means and the detected value of the generator frequency detecting means to zero, and the frequency signal generated by the frequency signal generating means for generating the generator. A frequency signal regulating unit that regulates the rotation speed within a set value range, and a governor control signal generation unit that generates a governor control signal according to a frequency signal out of the set value range among the frequency signals generated by the frequency generation unit. And a steam quantity control means for controlling the quantity of steam to the turbine according to the governor control signal generated by the governor control signal generation means, and a frequency signal restriction means for regulating the steam quantity within the set value range. And a excitation means for exciting the AC excitation winding of the generator according to the generated frequency signal. 5. A turbine rotation speed detecting means for detecting a rotation speed of a turbine connected to a generator having an AC excitation winding, and a system frequency detecting means for detecting a system frequency of an electric power system connected to the generator. A frequency signal generating means for generating a frequency signal for suppressing a deviation between a detected value of the turbine rotation speed detecting means and a detected value of the system frequency detecting means to zero; and a frequency signal generated by the frequency signal generating means for generating a generator. A frequency signal regulating unit that regulates the rotation speed within a set value range, and a governor control signal generation unit that generates a governor control signal according to a frequency signal out of the set value range among the frequency signals generated by the frequency generation unit. And a steam quantity control means for controlling the quantity of steam to the turbine according to the governor control signal generated by the governor control signal generation means, and a frequency signal regulation means. A generator control device comprising: an excitation unit that excites an AC excitation winding of the generator according to a frequency signal regulated within a range of a constant value. 6. A power generator that detects an output power of a generator having an AC excitation winding, and a generator from a deviation between a command value for an output of a turbine connected to the generator and a detected value of the power detector. Drive source rotation speed calculation means for calculating the rotation speed of the drive source to be driven, system frequency detection means for detecting the system frequency of the power system connected to the generator, calculated value of the drive source rotation speed calculation means and system frequency A frequency signal generating means for generating a frequency signal for suppressing the deviation from the detected value of the detecting means to zero, and a frequency for restricting the frequency signal generated by the frequency signal generating means within the set value range of the generator rotation speed. A signal control means, a governor control signal generation means for generating a governor control signal according to a frequency signal out of a set value range among the frequency signals generated by the frequency generation means, and a governor control Steam amount control means for controlling the amount of steam to the turbine according to the governor control signal generated by the signal generation means, and the AC excitation winding of the generator according to the frequency signal regulated within the set value range by the frequency signal regulation means. A generator control device comprising: an exciting means for exciting. 7. A voltage detecting means for detecting an output voltage of a generator having an AC excitation winding, a power detecting means for detecting an output power of the generator, and a deviation between a detected voltage of the voltage detecting means and a voltage command value. Voltage deviation calculation means, an amplitude command generation means for generating an amplitude command for suppressing the calculated value of the voltage deviation calculation means to zero, and a deviation between the detected power of the power detection means and the power set value. Power deviation calculating means, phase command generating means for generating a phase command for suppressing the calculated value of the power deviation calculating means to zero, generator frequency detecting means for detecting the frequency of the output signal of the generator, and generator Drive source rotation speed detecting means for detecting the rotation speed of the drive source for driving the motor, frequency deviation calculating means for calculating a deviation between the detection value of the drive source rotation speed detecting means and the detection value of the generator frequency detecting means, and a frequency Deviation calculator Phase signal generation means for generating a phase signal for suppressing the calculated value of the stage to zero, addition means for adding the phase signal generated by the phase signal generation means and the phase command generated by the phase command generation means, and addition Pulse signal generation means for generating a pulse signal from the phase command by the addition of the means and the amplitude command by the generation of the amplitude command generation means,
A generator control device comprising: a power converter that converts a direct current signal into an alternating current signal in accordance with the pulse signal generated by the pulse signal generator and converts the converted alternating current signal to excite the alternating current excitation winding of the generator. 8. A voltage detecting means for detecting an output voltage of a generator having an AC excitation winding, a power detecting means for detecting an output power of the generator, and a deviation between a detected voltage of the voltage detecting means and a voltage command value. Voltage deviation calculation means, an amplitude command generation means for generating an amplitude command for suppressing the calculated value of the voltage deviation calculation means to zero, and a deviation between the detected power of the power detection means and the power set value. Power deviation calculating means, phase command generating means for generating a phase command for suppressing the calculated value of the power deviation calculating means to zero, generator frequency detecting means for detecting the frequency of the power generated by the generator, and generator For calculating the deviation between the command value for the output of the turbine that rotationally drives the electric power and the electric power detected by the electric power detecting means, and the rotational speed for suppressing the deviation of the auxiliary electric power deviation calculating means to zero. Times A rotation speed calculation means, a frequency deviation calculation means for calculating a deviation between a calculated value of the rotation speed calculation means and a detection value of the generator frequency detection means, and a phase signal for suppressing the calculated value of the frequency deviation calculation means to zero. , Adder for adding the phase signal generated by the phase signal generator and the phase command generated by the phase command generator, and phase command and amplitude command generator generated by the adder Pulse signal generation means for generating a pulse signal from the amplitude command by the pulse signal generation means, and the AC excitation winding of the generator is excited by an AC signal obtained by converting a DC signal into an AC signal according to the pulse signal generated by the pulse signal generation means. A control device for a generator, comprising: a power conversion means. 9. An amplitude command regulation means for regulating an amplitude command input to the pulse signal generation means within a set value range, and a phase for regulating a phase command input to the pulse signal generation means within a set value range. 8. A command regulation means is provided.
Or the control device of the generator according to 8. 10. A governor control signal generating means for generating a governor control signal according to a phase command out of a set value range among the phase commands inputted to the pulse signal generating means, and a generation of the governor control signal generating means. 10. The generator control device according to claim 7, 8 or 9, further comprising: steam amount control means for controlling the amount of steam to be supplied to the turbine in accordance with the governor control signal from. 11. A generator having an AC excitation winding is rotationally driven according to the driving force of a drive source, the mechanical rotation speed of the generator is detected, and the frequency of power generated by the generator is detected. A generator operation control method for generating a frequency signal for suppressing the deviation of each detected value to zero and exciting the AC excitation winding of the generator according to the frequency signal. 12. A generator having an AC excitation winding is rotationally driven by a turbine, and when the AC excitation winding of the generator is excited by an output signal of an inverter, a mechanical rotation speed of the generator is detected and power is generated. The operation of a generator characterized by detecting the frequency of the generated power of the machine, generating a pulse signal for suppressing the deviation of each detected value to zero, and controlling the frequency of the output signal of the inverter according to this pulse signal. Control method. 13. A generator having an AC excitation winding is rotationally driven by a turbine, and when the AC excitation winding of the generator is excited by an output signal of an inverter, a mechanical rotation speed of the generator is detected and power is generated. A generator characterized by detecting the frequency of the generated power of the machine, generating a pulse signal for suppressing the deviation of each detected value to zero, and controlling the frequency and amplitude of the output signal of the inverter according to this pulse signal. Operation control method. 14. A designated generator among a plurality of generators is configured to have an AC excitation winding, and each generator is rotationally driven according to the driving force of a drive source, and the designated generator's AC When exciting the excitation winding with the output signal of the inverter, to detect the mechanical rotation speed of the specified generator and the frequency of the generated power of the specified generator to suppress the deviation of each detected value to zero. Is generated and the frequency of the output signal of the inverter is controlled according to the pulse signal.